The union said workers had been offered a non-consolidated payment of £500 dating from October 2017 and then a 2.8% increase from April 2018 until October 2019, as well as an additional £350 non-consolidated payment.

The ballot will begin on March 23 and run until April 13. Unite said if members vote for strike action, walkouts could start in late April.

Jamie Major, Unite regional officer, said: “Workers at Gatwick are disgusted with the company’s attitude. Their hard work means the company has achieved record profits, and they are dealing with record numbers of passengers, yet they have only been offered a real terms pay cut.

“Our members who are working harder than ever are not going to stand idly by and accept what will be a real terms pay cut.

“If GAL wants to avoid strike action which will inevitably lead to widespread disruption for passengers, then the management needs to return to the negotiating table and make a sensible offer."

A Gatwick spokesperson said: “Our focus remains on continuing discussion around pay in a positive and constructive manner directly with the trade unions and our employees.”